1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/fs/9p/vfs_dentry.c
4 *
5 * This file contians vfs dentry ops for the 9P2000 protocol.
6 *
7 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
8 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9 */
10
11 #include <linux/module.h>
12 #include <linux/errno.h>
13 #include <linux/fs.h>
14 #include <linux/file.h>
15 #include <linux/pagemap.h>
16 #include <linux/stat.h>
17 #include <linux/string.h>
18 #include <linux/inet.h>
19 #include <linux/namei.h>
20 #include <linux/idr.h>
21 #include <linux/sched.h>
22 #include <linux/slab.h>
23 #include <net/9p/9p.h>
24 #include <net/9p/client.h>
25
26 #include "v9fs.h"
27 #include "v9fs_vfs.h"
28 #include "fid.h"
29
30 /**
31 * v9fs_cached_dentry_delete - called when dentry refcount equals 0
32 * @dentry: dentry in question
33 *
34 */
v9fs_cached_dentry_delete(const struct dentry * dentry)35 static int v9fs_cached_dentry_delete(const struct dentry *dentry)
36 {
37 p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
38 dentry, dentry);
39
40 /* Don't cache negative dentries */
41 if (d_really_is_negative(dentry))
42 return 1;
43 return 0;
44 }
45
46 /**
47 * v9fs_dentry_release - called when dentry is going to be freed
48 * @dentry: dentry that is being release
49 *
50 */
51
v9fs_dentry_release(struct dentry * dentry)52 static void v9fs_dentry_release(struct dentry *dentry)
53 {
54 struct hlist_node *p, *n;
55 p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
56 dentry, dentry);
57 hlist_for_each_safe(p, n, (struct hlist_head *)&dentry->d_fsdata)
58 p9_client_clunk(hlist_entry(p, struct p9_fid, dlist));
59 dentry->d_fsdata = NULL;
60 }
61
v9fs_lookup_revalidate(struct dentry * dentry,unsigned int flags)62 static int v9fs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
63 {
64 struct p9_fid *fid;
65 struct inode *inode;
66 struct v9fs_inode *v9inode;
67
68 if (flags & LOOKUP_RCU)
69 return -ECHILD;
70
71 inode = d_inode(dentry);
72 if (!inode)
73 goto out_valid;
74
75 v9inode = V9FS_I(inode);
76 if (v9inode->cache_validity & V9FS_INO_INVALID_ATTR) {
77 int retval;
78 struct v9fs_session_info *v9ses;
79 fid = v9fs_fid_lookup(dentry);
80 if (IS_ERR(fid))
81 return PTR_ERR(fid);
82
83 v9ses = v9fs_inode2v9ses(inode);
84 if (v9fs_proto_dotl(v9ses))
85 retval = v9fs_refresh_inode_dotl(fid, inode);
86 else
87 retval = v9fs_refresh_inode(fid, inode);
88 p9_client_clunk(fid);
89
90 if (retval == -ENOENT)
91 return 0;
92 if (retval < 0)
93 return retval;
94 }
95 out_valid:
96 return 1;
97 }
98
99 const struct dentry_operations v9fs_cached_dentry_operations = {
100 .d_revalidate = v9fs_lookup_revalidate,
101 .d_weak_revalidate = v9fs_lookup_revalidate,
102 .d_delete = v9fs_cached_dentry_delete,
103 .d_release = v9fs_dentry_release,
104 };
105
106 const struct dentry_operations v9fs_dentry_operations = {
107 .d_delete = always_delete_dentry,
108 .d_release = v9fs_dentry_release,
109 };
110